1. Technical Field of the Invention
The present invention generally relates to communication schemes in a network. More particularly, and not by way of any limitation, the present invention is directed to a system and method for providing communications in a network using a redundant switching architecture.
2. Description of Related Art
In computer networks as well as telecommunications networks, availability refers to the percentage of time that the network is ready for immediate use. A traditional benchmark for availability is 99.999%, or “five 9s,” which translates into approximately 5.25 minutes of downtime per year. Five 9s availability is achieved through a combination of equipment reliability and network survivability. Other factors also play a role, including software stability and the ability to evolve or upgrade the network without taking the network out of service.
To satisfy these high expectations, telecommunications network nodes, e.g., signaling server systems that comprise a mesh of interconnected control elements (CEs), must be highly redundant, scalable, and capable of operating continuously under rugged ambient conditions and heavy traffic loads. In general, to provide redundancy for communications between CEs, primary and alternative switching planes are implemented. Primary switching planes provide the main mechanism of communication between two CEs. Upon detecting a fault in the primary switching plane, however, the server system provisions the alternative switching plane and switches the impacted traffic over to the alternative switching plane. The server system may then reconfigure the internal communication pathways accordingly and broadcast the affected routing tables.
The existing redundancy schemes are not without limitations, however. The time to detect a fault in the primary switching plane, the time to isolate the fault, the time to provision the alternative switching plane, and the time to switch over to the alternative switching plane each represent a potential source of data latency or, in more extreme cases, packet loss. Moreover, the administrative overhead created by CEs pinging each other in order to detect faults represents a drain on system resources. These drawbacks are particularly aggravating where a large number of CEs are interconnected in complex topologies.